1. Field of the Invention
This invention relates broadly to cassettes for feeding, counting and dispensing apparatus. More particularly, this invention relates to cassettes which store and feed discrete items, such as tablets, capsules or caplets.
2. State of the Art
In retail, hospital, and mail order medication dispensing, a large number of different prescriptions of single dose medications, such as tablets, must be filled. (Hereinafter, for purposes of brevity, reference to xe2x80x9ctabletsxe2x80x9d should be understood for purposes herein as being generic to tablets, capsules, caplets and any other solid dose medication). For prescriptions requiring small quantities of a medication, the prescription is often filled by hand; that is, a bulk container containing the prescription medication is removed from a shelf and opened. A quantity of the medication is poured into a tray and the medication tablets are counted by a pharmacist and then dispensed into a patient prescription bottle. The remainder of the medication in the tray is returned to the bulk container, the container is closed, and then replaced on the shelf.
Larger quantity prescriptions are often filled with the aid of a counting apparatus intended to more rapidly count different quantities of different tablets successively. For example, a prescription for ninety tablets of 10 mg Claritin(copyright) may need to be filled after a prescription for sixty tablets of 400 mg Motrin(copyright). Generally, there are two types of counting apparatus available for dispensing prescription medication from bulk containers of such medications: a preset counter and a pour-through counter.
With a preset counter, the pharmacist obtains a bulk container of a prescription medication from a shelf and then pours from the container a quantity of tablets into a hopper of the counting apparatus. The pharmacist then sets the counting apparatus to the number of tablets to be counted, e.g., ninety. Assuming at least the required number of tablets for the prescription has been poured into the hopper, the pharmacist waits while the counting apparatus counts the required number of tablets and dispenses the tablets into a patient prescription bottle. The excess tablets are discharged back into the bulk container, which is then replaced on the shelf. It has been found that the time taken to discharge the excess tablets can be equal to or greater than the time required to count the prescription. For that reason, the pour-through counter has proved more popular.
A pour-through counter does not include a hopper that temporarily stores the medication. Rather, the pharmacist pours tablets from a bulk container directly into a funnel which drops the tablets past a counter and dispenses them into a patient bottle. The pharmacist pours until the digital readout of the counter apparatus displays the required number of tablets, and then stops. As such, there is usually no excess. However, should an extra tablet or so fall into the funnel, the readout clearly indicates the extra number, and the excess can easily be removed by the pharmacist and returned to the storage container.
Both the preset and pour-through counter systems have a common drawback. Each prescription medication must be obtained from a bulk storage container located in stock, which must be opened prior to use and closed after use. In order to minimize the time taken to dispense a prescription, counter manufacturers have provided xe2x80x9ccassette countersxe2x80x9d for retail, hospital, and mail order pharmacies. Each cassette is designed for a specific size and shape capsule, tablet, or caplet. The cassettes are pre-filled by the pharmacist with bulk quantities of the appropriate prescription drugs, and are used to store bulk quantities rather than using the container supplied by the manufacturer. The prescription medication is then dispensed directly from the cassette. The use of cassettes eliminates the time needed to open the manufacturer""s original container, the time needed to return excess tablets to the container, and the time needed to close the container. Unfortunately, cassette counters are slow and prone to breaking tablets. Furthermore, when cassettes jam, as they often do, they are difficult to unclog. Often tablets spill uncontrollably from the cassette during attempts to unclog a jam. Further, since the cassettes used in existing cassette systems are specific to the tablet being dispensed, each time a pharmacist wants to count a new drug, a new cassette designed for that specific medication must be obtained. In addition, some prescriptions are filled infrequently and it is not economically feasible or practical to have a dedicated cassette for every solid dose medication in the pharmacy.
It is therefore an object of the invention to provide a system for counting and dispensing discrete objects such as tablets, capsules and the like which permits storing discrete objects in a manner in which the objects may be quickly dispensed.
It is another object of the invention to provide a counting and dispensing system which uses cassettes which are not customized to a particular tablet or capsule.
It is a further object of the invention to provide a counting and dispensing system which uses cassettes which are relatively inexpensive to manufacture.
It is an additional object of the invention to provide a counting and dispensing system which is not subject to jamming by discrete objects being counted.
Another object of the invention is to provide a counting and dispensing system which provides rapid counting of the discrete objects.
A further object of the invention is to provide a counting and dispensing system which can also be used without a cassette.
An additional object of the invention to provide a counting and dispensing system which has the benefits of two different modes of operation, as a pour through counter, as well as a preset counter.
Yet a further object of the invention is to provide a counting and dispensing system which can also be used with a bowl feeder.
Yet another object of the invention is to provide a counting and dispensing system which is adapted for rapid exchange of cassettes and bowl feeders.
It is yet an additional object of the invention to provide a counting and dispensing system which functions with high reliability.
In accord with these objects, which will be discussed in detail below, an object counting and dispensing system is provided which includes a vibration system which substantially circularly vibrates in a horizontal circular plane, a mounting assembly for coupling a cassette to the vibration system, a chute configured to receive discrete objects from either the cassette or a funnel and dispense the objects to a patient bottle, and an object sensing system which senses and counts objects fed into the chute.
Each cassette includes a base and a stepped side wall which together define a central open reservoir portion and at least one substantially planar covered tray portion surrounding the reservoir portion. A lid is removably coupled over the reservoir portion. The reservoir portion is adapted to store tablets and feed the tablets through a path into the tray portion. The tray portion has a peripheral exit and guides the fed tablets toward the exit when the cassette is vibrated by the vibration system. The tray portion optionally includes a peripheral track which facilitates the guidance of tablets having non-flat surfaces toward the exit. A leaf spring gate closes the exit and is automatically opened by a permanent magnet attached to the tip of a solenoid when the cassette is attached to the mounting assembly, and closed when the cassette is removed therefrom. When the last tablet in a batch has been counted, the magnet is retracted and the leaf spring closes the exit of the cassette. The leaf spring also closes the cassette when the cassette is removed from the mounting assembly and moved away from the magnet. Each cassette includes a lower metal portion at which the cassette is mounted to the mounting assembly. Cassettes are mounted to the mounting assembly in a manner which permits rapid and secure coupling and decoupling. Preferred coupling means include an electromagnetic coupling system.
Each cassette is able to feed and guide a range of sizes and shapes of tablets toward the exit. As such, only a few standard sizes of cassettes are needed to accommodate a wide range of discrete objects for which the counter is primarily adapted: tablets, capsules, caplets, etc. When used with the cassette, the system functions as a preset counter wherein the counter is preset to count a desired number of tablets, and the counter then feeds and counts the exact number of tablets from the cassette.
As briefly discussed above, according to another aspect of the invention, the system can be used without the cassette and operate as a pour-through counter in which tablets are poured into the funnel.
In addition, a universal bowl feeder can be attached to the mounting assembly, preferably in the same manner as the cassettes. The bowl feeder can accommodate prescriptions which are not provided with their own cassette and for which it is desired to preset the number of tablets to be counted.
Additional objects and advantages of the invention will become apparent to the skilled in the art upon reference to the detailed description taken in conjunction with the provided figures.